60 grams organic extra coarse wholewheat starter
300 grams water, tepid (75°F)
300 grams organic white stoneground flour
45 grams organic light malthouse flour
45 grams organic wholemeal spelt
8 grams fine sea salt
Prepare the leaven: 8 to 12 hours before you mix your dough, prepare the leaven. Place the refreshed starter and water in a large bowl and stir to break up the starter. Add the flour and mix with a spoon until no dry lumps remain. Cover and allow to ferment at room temperature until you are ready to mix your dough.
Mix the dough: When bubbles break the surface of the leaven, it smells ripe, and it has swelled considerably in size, add the water and stir to combine. Measure the flours into the bowl and use your hands to mix and squeeze the dough in a circular motion until no dry lumps remain. Cover and rest the dough for 20 minutes, allowing the flour to fully hydrate before adding the salt. Sprinkle the salt evenly over the surface of the dough and mix well to combine. This is an ideal time to observe your flour performance, as you may need to make adjustments with the addition of water. If the dough feels resistant to mixing and difficult to work inside the bowl, add more water in 20 to 25 gram increments, thoroughly mixing it in with the salt until the dough is no longer slick on the surface. The dough should feel supple and somewhat sticky at this point.
Bulk fermentation: Place the dough back into the bowl and cover once more. Set the bowl aside in a warm location (ideally 75°F) to bulk ferment for about 3 1/2 to 4 hours (perhaps 1/2 hour shorter in the summer, possibly 1/2 hour longer in the winter months). During this time, stretch-and-fold the dough in the bowl to help develop the gluten network essential for trapping fermentation gases. To do this, wet your hands first to prevent the dough from sticking and gently slide your fingers of both hands under the dough. Release the dough from the sides of the bowl and gently fold it to the center. Rotate the bowl and repeat 3 to 4 more times until you have worked your way around the dough. Repeat this process every 30 to 45 minutes, being especially careful toward the end of bulk fermentation not to aggressively handle or deflate the dough. You should notice it progress from a ‘shaggy mass’ at the beginning of the mix to exhibiting a more cohesive and smooth character by the end of bulk fermentation.
Shape the dough: When the dough has increased by at least 1/3 of its size and you see fermentation bubbles breaking the surface (about 3 1/2 to 4 hours or longer depending on room temperature), it is time to shape the dough. This is done in two stages: pre-shape with a short bench resting period, followed by a tighter final shaping. Using a bowl scraper, swiftly remove the dough from the bowl and place on a lightly floured surface. Using your hands, bring the top of the dough to the center, followed by the bottom, and two sides in a north, south, east, west motion. Tuck the resulting four corners to the middle as well, resulting in a slightly rounded form. Using your bench scraper, release the dough from the surface and flip it over seam side down. Cover with plastic and allow to bench rest for 10 to 30 minutes until it visibly relaxes.
To final shape, use the bench scraper to flip the dough over onto a lightly floured surface, seam side up. Starting from the top, tuck the right side to the center, holding it in place while you bring the left side to the center overlapping with the first. Repeat this side-to-side stitching until you reach the bottom of the dough. Roll the bottom toward the center, repeating as necessary until the seam is facing down, tucking as you go to create tension. Flour the top of the loaf generously. Use your bench scraper to pick up the dough and flip it over, seam side up. Cradle it into your proofing basket before covering with a cloth. Cover with plastic and place in the refrigerator to retard for at least 8 hours or up to 24 before baking.
Before bake your loaf: Remove your loaf from the refrigerator and allow to come to room temperature for about 1 hour. When it is ready to bake, it should feel like an inflated water balloon when gently poked with your index finger. The impression should linger in the dough rather than immediately bouncing back. Depending on the temperature of your refrigerator and your kitchen, this may take more or less time to final proof before baking.
Preheat a Dutch oven to 480°F on the middle rack for 20 minutes. Cut a piece of parchment paper to fit the Dutch oven and carefully flip your loaf onto it seam side down. You may choose to sprinkle a little flour onto the surface before scoring to get a more graphic contrast, dusting off any excess. Score the top of the loaf with a razor blade about 1/4-inch deep to allow the loaf to fully expand in a controlled manner while baking. You may add additional decorative scoring flourishes but be aware that the loaf will continue to spread before going into the oven as you do so. Carefully lower it into the preheated Dutch oven, position the lid, and return it to the oven. Bake with the lid on for 20 minutes. Remove the lid and lower the oven temperature 10 to 15°F. Bake for another 15 to 20 minutes until the crust is a deep, rusty brown or darker if desired. Cool completely on a wire rack before slicing.